Apparatus for loading pipe casting molds



Dec. 17, 1963 H. D. BOGGS ETAL 3,114,173

APPARATUS FOR LOADING PIPE CASTING MOLDS Original Filed June 28, 1956 9Sheets-Sheet l "Zn/Ma, 9%; W

ATTORNEYS Dec. 17, 1963 H. D. 50668 ETAL APPARATUS FOR LOADING PIPECASTING MOLDS 9 Shets-Sheet 2 Original Filed June 28, 1956 Dec. 17, 1963H. D. 50665 ETAL APPARATUS FOR LOADING PIPE CASTING MOLDS Original FiledJune 28, 1956 9 Sheets-Sheet '3 m bsk ATTORNEYS f w. x A

Dec. 17, 1963 H. D. BOGGS ETAL APPARATUS FOR LOADING PIPE CASTING MOLDSOriginal Filed June 28, 1956 9 Sheets-Sheet 4 Dec. 17, 1963 H. D. BOGGSETAL APPARATUS FOR LOADING PIPE CASTING MOLDS 9 Sheets-Sheet 5 OriginalFiled June 28, 1956 ATTORNEYS um: :4 AMA Dec. 17, 1963 H. D. BOGGS ETAL4,173

APPARATUS FOR LOADING PIPE CASTING MOLDS 7 Original Filed June 28, 19569 Sheetg-Sheet 6 A\ on u I! 1 \l w k- $12 fi O w ,0 1 92 ET r(\ BY Z ZFATTORNEYS 9 Sheets-Sheet 7 H. D. BOGGS ETAL APPARATUS FOR LOADING PIPECASTING MOLDS Dec. 17, 1963 Original Filed June 28, 1956 INVENTORS FeaL/Vgo n, /r

ATTORNEYS Dec. 17, 1963 H. D. BOGGS ETAL APPARATUS FOR LOADING PIPECASTING MOLDS 9 Sheets-Sheet 9 Original Filed June 28, 1956 INVENTORSBgp ns fierZeriD. Fred A .M

ATTORNEYS United States Patent 3,114,173 APPARATUS FUR LGADHIG PIPE(IASTIN G MOLDS Herbert D. Boggs, Brea, Calif., and Fred L. Magoon, Jr.,Longview, Tex., assignors, by mesne assignments, to H. D. Boggs Company,Ltd, Gmaha, Nehin, a limited partnership Original application June 23,1956, Ser. No. 594,565, now Patent No. 2,997,737, dated Aug. 29, 1961.Divided and this application Dec. 29, 196i), Ser. No. 79,295

10 Claims. (Cl. 18-26) This invention relates to methods and apparatusfor the manufacture of plastic pipe, and, more particularly, ofcentrifugally cast plastic pipe which is reinforced by woven glassfilaments.

The arts concerning the manufacture of fibrously reinforced plasticpiping and, more specifically, piping formed from thermosetting plasticmaterial, such as thermosetting resins, and reinforced with variousfibrous elements, and more specifically with fibrous elements formed ofglass filament formations, have been extensively disclosed and discussedin detail in the copending applications of H. D. Boggs, Serial No.200,193, filed December 11, 1950, now Patent No. 2,776,450, Serial No.264,976, filed January 4, 1952, now Patent No. 2,785,442, and Serial No.459,092, filed September 29, 1954-, now abandoned, and in the followingcopending applications as signed to a common assignee: Kenneth A.Schafer, Serial No. 280,766, filed April 5, 1952, now abandoned, andLewis Perrault, Serial No. 404,329, filed January 15, 1954, nowabandoned.

It is Within the contemplation of this invention to prepare uniformlyformed, fibrously reinforced, plastic piping of the type illustrated ordiscussed in some of these applications, as well as provide improvementsin the apparatus and methods, for preparing such plastic pipe, describedin others of these applications.

It is therefore an object of this invention to provide new and improvedmeans, and new and improved combinations of means, for manufacturingfibrously reinforced plastic pipe.

It is another object of this invention to provide new and improvedapparatus for manufacturing fibrously reinforced plastic pipe whichprovides greater uniformity of product and better quality control.

It is another object of this invention to provide new and improvedapparatus for manufacturing fibrously reinforced plastic pipe, whichapparatus can be easily and continuously operated by a small laborforce.

More particularly, it is an object of this invention to provide new andimproved means for the insertion of the elongated fibrous reinforcementelement into a mold wherein the pipe is to be formed by the introductionof a plastic material into and about the fibrous reinforcement element.

These and other objects of this invention will be fully understood fromthe following detailed description of a typical preferred form andapplication of the invention, throughout which description reference ismade to the accompanying drawings in which:

FIGURE 1 is an elevational view, with portions broken away, to showdetails of interior construction of a mandrel assembly;

FIGURE 2 is an end View of the mandrel taken along lines 2-2 of FIGURE1;

FIGURE 3 is a section taken along lines 33 of FIGURE 1;

FIGURE 4 is an elevational view of the braiding and cleaning apparatus;

FIGURE 5 is an elevational view of the mold-feeding assembly;

3,lld,l?3 Patented Dec. 17, 1963 FIGURE 6 is a plan view of themold-feeding assembly;

FIGURE 7 is an elevational view, partially in section, illustratingdetails of the means for locking the moldfeeding assembly in position;

FIGURE 8 is a section taken along lines 8-8 of FIG- URE 6;

FIGURE 9 is a vertical sectional view of a collar;

FIGURE 10 is a section taken along lines Iii-1t) of FIGURE 9;

FIGURE 11 is a vertical sectional view of the collar illustrated inFIGURES 9 and 10 being threaded into position at the mold end of themold-feeding assembly;

FIGURE 12 is an elevational view, partially in section, of the moldassembly;

FIGURE 13 is an elevational view, with portions broken away toillustrate interior details, of the resin impregnating means;

FIGURE 14 is a plan view of the air-blowing assembly;

FIGURE 15 is an elevational view of the air-blowing assembly;

FIGURE 16 is an end view of the air-blowing assembly;

FIGURE 17 is a schematic diagram of the air pressure system used inenergizing the air-blowing assembly;

FIGURE 18 is an elevational view of the pipe-ejecting assembly;

FIGURE 19 is a plan view of the pipe-ejecting assembly;

FIGURE 20 is a section taken along lines Zil-Ztl of FIGURE 19; and,

FIGURE 21 is a section taken along lines 21-21 of FIGURE 20.

General Description Before making a detailed disclosure of the apparatusand methods for forming plastic pipe which constitute this invention, ageneral description will be presented.

The apparatus of this invention includes a mandrel assembly upon whichreinforcement elements in the form of concentric sleeves or tubes ofglass fiber are woven or braided by conventional braiding apparatus. Themandrel assembly consists of a cylindrical mandrel core enclosed Withina cylindrical mandrel sleeve, the latter being separated into severallongitudinally extending segments. A plurality of fibrous tubes arebraided in concentric layers on the exterior of the assembled mandrel,with each of the fibrous tubes being subjected to a heat cleaningtreatment prior to being circumscribed by the next tube. Each mandrelassembly has a length equal to a length of the sections of the pipe tobe formed and is arranged to smoothly abut, in tandem relation, againstanother mandrel assembly to form, in effect, a continuous mandrel, sothat the braiding machines form continuous lengths of concentric fibroustubes which are subsequently cut oif in lengths approximating that ofeach individual mandrel assembly.

In other words, after the concentric fibrous reinforcement elements havebeen formed upon the tandemly arrange-d mandrels, the mandrels areseparated with rein forcement elements being cut at the points ofseparation. Thereafter each mandrel, which is circumscribed by areinforcement element consisting of two or more concentric woven fibroussleeves or tubes, is placed on a mold-feeding assembly, which serves aplurality of pipe casting molds. The mold-feeding assembly is alignedwith, and selectively positioned relative to, a selected mold and thenmechanisms thereon are opera-ted to insert the mandrel assembly,together with the woven reinforcement element, into the mold. Othermechanisms on-the moldfeeding assembly are then operated to withdraw thecore of the mandrel assembly from the mold, leaving a major portion ofthe mandrel sleeve, together with the fibrous reinforcement element,therewithin. The remaining elements or segments of the mandrel sleeveare then removed by hand, or by other means, to leave the woven fibrousreinforcement element smoothly disposed against the inner periphery ofthe cylindrical casting mold.

This invention also includes means for introducing heat settablematerial, such as thermosetting resins and the like, through the ends ofthe molds and uniformly along the entire length of the interiors thereofin a manner which will not disturb the placement of the individualfibers of the woven fibrous reinforcement element disposed therewithin.

This invention further includes means for centrifugally casting plasticimpregnated fibrously reinforced piping by providing means forconcurrently heating and rotating the mold, as well as for concurrentlycooling and rotating the mold.

It is also within the contemplation of this invention to provide meansfor uniformly heating the contents of the mold, prior to the heatsetting of the thermosetting material, by blowing heated air throughalternating ends of the mold.

It is also within the contemplation of this invention to provide meansfor uniformly cooling newly formed plastic impregnated, fibrouslyreinforced pipe while it is undergoing an exothermic reaction within themold, just after it has been heat set into its final physical form, byblowing air through the ternating ends of the mold.

There is a pipe ejecting assembly, arranged to serve a plurality of thecasting molds, which is aligned with a mold in which the plastic pipehas been formed, and which carries mechanisms thereon to withdraw thenewly formed plastic pipe from the molds in a manner which eliminatesany danger of damage to the pipe.

For the sake of clarity, the various apparatus and means brieflydescribed hereinabove will be separately described and illustrated.

The Mandrel Assembly Referring to FIGURE 1, the mandrel assembly,generally indicated at 9, includes a mandrel core 16 which is formed ofcylindrical stock and may be hollow to save material and avoid excessiveweight. One end of the mandrel core It? has a cylindrical projection 12.of reduced diameter, and the other end is formed to define a cylindricalsocket 14, which is dimensioned to snugly, but slidably, receive aprojection 12 from another identical mandrel. The bottom or end wall 16of the socket 14 has a centrally located threaded aperture 18 therein,although if the mandrel core it is formed of solid stock, the aperturewill be replaced by a similarly located threaded socket.

The free end of the projection 12 may be beveled, as at 2%, and themouth of socket 14 may be beveled, as at 22, to facilitate the entranceof a projection into the socket. Similarly, the mouth of the aperture 18may be beveled, as at 26, to aid in the reception of either a projection12 of another similar mandrel or a member which will be describedhereinafter. It should be noted that the axial length of each projection12 is somewhat greater than the depth, or axial length of each socket14, the difference in length being substantially equal to the axiallength of a collar, generally indicated at 24, formed by the endportions of the slips 2'7, 28, 29, and 3d (FIG- URES 2 and 3), whichwill now be described.

Each mandrel is provided with a plurality of, and in a preferredembodiment four, slips 27, 28, 29, 36. The slips 27, 28, 29 and 59 areformed of relatively thin lengths of metal, each having an arcuate crosssection, and the slips of a given mandrel, when properly arrangedtogether, form a cylindrical sleeve which encloses the exteriorperiphery of the mandrel core 10 and which extends the entire lengththereof. Each of the slips has a shoulder 32 welded, or formed, thereonto extend radially inward, relative to the arcuate curvature of asection thereof. The free end of each of the shoulders 32 is arcuatedlycurved, about the same center as the areuate curve of its slip, so thatthe combination of the shoulders of all of the slips 2'7, 23, 29 and 3t}fitted on a given mandrel core ill form an inwardly extending,circumferential collar, generally indicated at 24, on the sleeve formedthereby. Actually, as best shown in FIGURE 2, this circumferentialcollar is only approximated and is not complete because theradially-inwardly extending neighboring surfaces 25 of some of theshoulders 32 are not parallel, but rather diverge, by perhaps 30, asthey extend inwardly. The approximated collar 24 has an interiordiameter somewhat greater than the exterior diameter of the projection12, and, as best shown in FIG- URE 1, the thickness of the approximatedcollar 24, that is to say its axial length, is approximately equal tothe difference between the length of the projection 12 and the depth,i.e., axial length, of the socket 14. It will therefore be seen thatwhen identical mandrel cores 10, each fitted with an enclosing sleeveformed by the slips 27, 23, 23 and 30, are tandemly aligned, and thenmoved into axial abutment, the several mandrel assemblies 9 will form anessentially continuous mandrel having a substantially smooth andunbroken cylindrical exterior.

While in the illustrated preferred embodiment there are four slips 27,'28, 29 and 30, it is within the contemplation of this invention thatthere may be more or less. In any event, one of the slips 27, which ispreferably small, i.e., narrow, is permanently affixed, as by screws 36(FIGURE 1), to the mandrel core 10. The other slips are held in positionby a circumferential tension spring 38, one or more of which maycircumscribe the entire mandrel assembly 9.

Referring to FIGURE 1, it will be seen that each shoulder 32 has a smallpin 39 on the inner surface thereof, that is on the surface abutting theend surfaces of the mandrel core 10, and that the end surface of thecore has a complementary socket to snugly receive this pin.

The Braiding and Cleaning Apparatus Referring to FIGURE 4, the tande-mlyaligned and axially abutting and interfitting mandrel assemblies 9 arefed, by hand or by any means, onto a power driven pinch roll stand 50,which urges them through a series of alternating braiding and heatcleaning devices, generally indicated at 52. and 54, respectively. Thebraiding machines 52, which may be of any standard form and design, andwhich are merely outlined in FIGURE 4, are equipped with a number ofbraider heads 56, and in a preferred embodiment with 96 braider heads,to weave glass filament threads 57 into a braided tube 53 about themandrel assemblies 9. in some cases the braiding machines will includemeans to lay a plurality of separate strands on the surface of themandrel assembly to extend longi tudinally thereof in peripherallyspaced relationship, the braiding means and the last mentioned meansbeing cooperatively arranged to braid the woven strands about thelongitudinally extending strands. The braiding machines 52 and the pinchroll stand 56 are all powered by a common drive shaft Sy so that thereis a fixed relation between the speed of t e rotation of the braiderheads 56 about the lengths of mandrel assemblies 9 and the axialmovement of these mandrel assemblies through the braiding machines.When, in accordance with this invention, successive layers or plys ofthe tubular reinforcement element, generally indicated at 66, aredesired, several braiding machines 52 are arranged in alignment to formsuccessive plies upon the substantially continuous mandrel assemblies 9passing therethrough, one such machine bein g provided for each ply. Themandrel is supported by rollers 61, one being located on each axial sideof each braiding machine.

Standard glass filament threads which are currently available aremanufactured and supplied to the industry with a coating, such as starchor oil, on the filaments to act as a lubricant during subsequenthandling. It has been discovered that it is desirable to remove all suchcoatings from the filaments prior to the using of reinforcing elementsformed therewith in the casting of fibrously reinforced plastic pipeswith thermosetting resins, as such a coating serves to prevent, or atleast retard, the forming of a satisfactory adhesion or bond between theresin and the glass fibers. For instance, it has been found that certaincoatings will form air bubbles on the glass filaments during the curingof the resin. As has been explained in the copending application, Boggsapplication No. 459,092, filed September 29, 1954, a satisfactory bondbetween the resin and the individual fibers of the reinforcement elementis essential if a sufiiciently strong, non- Weeping, and pressureresistant pipe is to be formed.

It is therefore within the contemplation of this invention to removesuch a coating by the provision of a heat cleaning device, generallyindicated at 54, between each of the braiding heads. Due to the factthat glass is a good insulator, it is preferable to remove this coating,when present after each ply is formed or braided on the mandrel andhence, to provide a separate cleaning oven 62 at the discharge side ofeach braiding machine. It has been found that due to the high heatconductivity of the metallic mandrel assembly 9, a higher oventemperature is required to remove the coating on the first layer or plyon the mandrel, than is required in the subsequent ovens because thesecond and subsequent plys are insulated from the mandrel by the firstply, or the inner plies. As a filament temperature of approximately 600-850 F. is required to satisfactorily destroy the coating on the glass,it has been found that satisfactory results may be obtained when thetemperature of the first oven, which heats the innermost ply, is in therange of 150i)'l800 F., and when the temperature of the successive ovensare in the range of 1500 P. All of the oven temperatures set forth areon the basis of the sleeve being braided, and hence, the continuousmandrel being moved, at a speed of 33 to 61 inches per minute, and it isbelieved that the oven temperature ranges may be varied to some degree,depending upon the speed of the mandrel, the length of the oven, thethickness of the braid, and the particular coating which is used uponthe glass fibers being braided.

In a preferred embodiment of this invention, the heatcleaning device 54consists of an elongated cylindrical chamber or oven 62 surrounding theaxially moving mandrel assemblies 9 which are covered with one or morelayers of braided glass fiber tubing 58. Each oven is connected bysuitable ducts with a small furnace, preferably a gas furnace 63, whichis supplied with gas and an excess of combustion air by compressor-mixer64. The combustion products and the heated excess air travel to the oven62 and thence to a collection ring 65 and out through vent 66. It shouldbe recognized that the specific design of the furnace and oven can beconsiderably varied within the scope of this invention and that anyother similar arrangement may be utilized to bring the temperature ofthe filaments of the tube 58, or filaments of the outside tube if thereare more than one, up to a temperature of a range of 600 to 850 P. sothat the coating of starch and oil on the glass fibers will carbonize.It has been found that once the starch and oil coating on the fibers hasbeen carbonized, it no longer affects the bond between the glass and theresin, and, further, that the carbon acts saitsfactorily as a filler inthe pipe body. It will now be understood that it may be desirable tocoat the outer surface of the mandrel assembly 9, i.e., the outersurface of the slips 27, 23, 29 and 30, with a silicone release agent,such as a stantard commercial high temperature silicone grease, by meansof a felted brush 67, as it leaves the pinch roll 59, so that theinnermost tube will not adhere to the mandrel assembly and thus hinderthe subsequent removal thereof, in a manner which will be described indetail hereinafter.

It may be desirable to pre-clean the exterior of the mandrel assembly bymeans of a circumferential wire brush 67a which is formed to receive abelt drive 6712 which is, in turn, rove over a spindle 67c, fitted onpower shaft 59, so that the Wire brush will be positively actuated torevolve about the mandrel assembly.

It will now be understood that tension spring 38, which helps hold theslips 28, 29' and 30 on the mandrel core prior to the first bnaidingoperation, must not be allowed to enter the braiding machines. A guard67d is therefore fitted on the entry side of the pinch roll stand tocatch these springs.

After an individual mandrel has been passed through several braiderheads and ovens, and has received the desired number of plies or layersof braided tubing, the continuous reinforcement element 60, consistingof the concentric fibrous tubes 58, is cut at the points of intersectionof a given mandrel assembly 9 with its neighboring mandrel assemblies.The ends of the reinforcement element 61 are tied or taped to preventthe braid from unraveling and the mandrel assembly is then transportedto the mold-feeding assembly.

The Mold-Feeding Assembly Referring to FIGURES 5 and 6, it will be seenthat a mold-feeding assembly, generally indicated at 68, includes anelongated base frame, generally indicated at 70, which is mounted onflanged wheels 72 for movement along relatively transversely extendingfixed rails 74- so that the entire mold-feeding assembly can betransversely moved between a number of positions corresponding to anumber of casting molds, generally indicated at 76. In a preferredembodiment, the transverse movement of the entire mold-feeding assembly63 is selectively controlled by a hand operated sprocket wheel 78 whichis connected by a chain drive 86 to a sprocket 82 on the shaft 84, uponwhich the wheels 72. are non-rotatably mounted. As will be evidenthereinafter, it is quite important that the entire mold-feeding assembly68 be properly aligned with the axis of the particular mold which it isto service and the means for attaining this exact alignment will now bedescribed.

Depending from the mold-feeding assembly base frame is an air lockassembly, generally indicated at 86 (FIGURES S and 7), consisting of apneumatic cylinder $8 having :a piston rod 90 extending therefrom, withthe entire assembly being so located that when the piston rod 90 isbeing pneumatically urged outward, it bears against the web 92 of one ofthe fixed nails 74. The web 92 of this rail 7 4 has one aperture 94drilled therein, or a recess formed therein, at the same level as thepiston rod 90, for every mold 76 which is to be served. The aperture 94is dimensioned to receive the piston rod 91 in a manner to lock theentire mold-feeding assembly 68 against further transverse movement, andis so transversely (of the moldfeeding assembly 68) located as toreceive the piston rod when the entire mold-feeding assembly is properlyaligned with a given mold. The air lock assembly -86 may be remotelycontrolled, by a valve 96 located near the sprocket wheel '78 (FIGURES 5and 6), to urge the piston rod 90 outwardly, or towards an extendedposition, when it is intended to lock the mold-feeding assembly 68 in adesired position, that is to say in alignment with a particular mold,and also to urge the piston rod to a retracted position, clear of theapertures 94, when it is desired to unlock the mold-feeding assemblybefore moving it to a new position.

Referring again to FIGURES 5 and 6, the transversely movable base frame70, which consists essentially of a pair of suitably braced,longitudinally extending, spaced parallel rails 194 which may be formedof I-beams or the like, has a second frame, generally indicated at 102,which consists essentially of a pair of suitably braced, longitudinallyextending, spaced parallel rails 104, which may be formed of I-beams orthe like, mounted thereon. The second frame 102 is supported on flangewheels 1% which are arranged to roll along rails 100 when the secondframe is moved longitudinally of the base frame 70. Such movement isobtained by a pneumatic cylinder 1128, depending from the second frame1132, having the free end of its piston rod 1119 fixed to a fixedupstanding member 112 on the base frame 70. The pneumatic cylinder 1118is double acting and is coupled, by suitable lines, to a three-waycontrol valve 114 located on the operated panel 115.

A mold-feeding carriage, generally indicated at 116, is disposed uponthe rails 104 to move longitudinally thereof on wheels 118. Themold-feeding carriage 1-16 is positively actuated to move longitudinallyof second frame 102 by a chain drive 12% extending longitudinally of therails 104, and approximately midway thereoetween, at a level slightlybelow their upper surface. The chain drive 120 is secured, at each end,to the mold-feeding carriage 116, as by draw bolts 122 (FIGURE 8), andextends around an idler sprocket 124- mounted at the mold end of therails 164 and around a power sprocket 125 mounted at the opposite end ofthese rails. The power sprocket 125 is non-rotatably fixed to a coaxialdrive sprocket 126 which is, in turn, engaged by chain drive 128 to asprocket 13% fixed on the shaft of reversible air motor 13-2, the latterbeing remotely controlled by a three-way valve 134 located on theoperating panel 115.

As the mold-feeding carriage 1-16 serves to convey an individual mandrelassembly 9, circumscribed by a reinfor-cement element 60, consisting ofone or more layers or plies of braided tubing, into a waiting casingmold 76 and, further, to withdraw a mandrel core from a mold, there areprovided several mandrel supporting rollers 136 to bear the weight ofthe mandrel during the periods when it is on, or partially on, themold-feeding as sembly 68.

Referring more particularly to FIGURE 3, cantilevered from themold-feeding carriage 116 is a tube 138 of heavy stock extending towardthe mold end of the rails 111 The tube 138 has an exterior diametersubstantially equal to the exterior diameter of the mandrel core 10, andthe free end thereof is formed with a projection 141) of reducedexterior diameter which is dimensioned to fit into the socket 14 of themandrel core. Loosely fitted within the tube 138 is a mandrel engagingshaft 142 having a threaded end 141 which normally extends outwardlyfrom the reduced end 146 of the tube, that is, the end towards thecasting molds 76. This threaded end 141 is so dimensioned that itsthreads will operatively engage the threaded aperture 18' in the bottomor end of socket 14. The opposite end of the mandrel engaging shaft 142extends without the opposite end of tube and has a hand wheel 143 fittedthereto.

A collar 144 having an internal diameter slightly greater than theexterior diameter of the mandrel core 1%, and somewhat smaller than theexterior diameter of the a sembled slips 27, 28, 29 and 31B, is looselyfitted on the mold end of the tube 138. As shown in FIGURES 9 and 10,the collar 144 is formed with a longitudinally extending keyway 146which has a width and depth slightly greater than the width and heightof fixed slip 27. That is to say, the collar interior, including itskey- Way 146, is so dimensioned as to allow the mandrel core 10,together with the fixed slip 27, to move therethrough when the keyway isproperly indexed with the fixed slip. The end of the collar locatednearest the mold 76 has a short counterbore dimensioned to receive theentire mandrel assembly 9, the counterband defining a paraannularabutment 145, the annulus defined by the abutment being broken by keyway146. The exterior of the collar 144 has a few turns of raised heavy-dutythreads 147 formed thereon on the end furtherest from the mold '76 forreasons which will be apparent hereinbelow. The exterior of tube 138 hasa key 1 28 mounted thereon to fit into keyway 14-6 to prevent relativerotation between the collar 144 and the tube 138.

In operation, the entire mold-feeding assembly 63 is aligned with theparticular mold 76 to be supplied with a reinforcement element 69 andthe second frame is correctly positioned, longitudinally of the baseframe, in a manner which will become evident hereinafter. A mandrelassembly 9, which has been passed through the alternating braidingmachines 52 and heat cleaning ovens 54, and which has reinforcementelement 60, consisting of a number of concentric braided fibrous tubes,formed thereon, is placed upon the mandrel supporting rollers 136, withthe end having the recess 14 facing the moldfeeding carriage 116, whichis then disposed at the ends of the rails 104 which are furtherest fromthe mold 76. The mandrel assembly is so indexed that the fixed slip 27is angularly aligned with the keyway 146 of the collar 14 Themold-feeding carriage 116 is then moved, by air motor :132, toward themold '76 to a position wherein the reduced end 14%} of the tube 138 fitswithin the recess 14 of the mandrel core 10. The threaded end 141 ofshaft 142 will then be abutting and engaging the first turn of thethreads of aperture 18. The shaft 142 is then rotated, by means of handwheel 143, to edect a firm threaded engagement between the shaft 142 andthe mandrel core 1%. The mold-feeding carriage 116, together with themandrel assembly 9 affixed thereto, and the collar 144 mounted thereon,is then moved, by air motor 132, toward the mouth of the mold 76 untilthe mandrel assembly and its surrounding reinforcement element 6! areentirely within the mold 76.

Referring more particularly to FIGURE 11, as the mandrel assembly 9moves toward the mold 76, the end thereof opposite from the mold-feedingcarriage 116 passes through the aperture of a large nut 149 which ismounted for rotation about a fixed axis, corresponding to the axes ofthe mandrel assembly 9, the tube 138', the collar 144, and the mold '76,by the loose fit of its radially extending, circumferential flange 15%within a corresponding annular groove 152, formed by a flanged angularring 154; and an apertu-red plate 156, the latter member being mountedon, and fixed to, the mold ends of rails 184. The nut 149 has a portionof its exterior periphery formed as a sprocket wheel 157 which isengaged, by a chain drive 158, with a drive sprocket 1612' (FIGURE 6),the latter being operated by a coaxial hand wheel hi1 which is locatedat the operating panel 115.

The threads of nut i149 ane dimensioned for engagement with raisedthreads 147 of the collar 144. After the mandrel assembly 9 iscompletely within the mold '76, the collar 144 is moved axially, byhand, or other means, along the tube 138 until it extends through thenut 14% and its mold and almost touches the slips 27, 28, 29 and 30. 'Itwill now be understood that if the second frame 1112 has been correctlylongitudinally positioned along the rails of the base frame 70, thedistance between the mold end of the collar 144 and the slips will bethe thickness, i.e., the axial length, of the threads 147 of the collar.Stated otherwise, the correct position of the second frame 102 will bedetermined by the length of the collar 144'.

At this time the collar 144 is so indexed that its longitud-inallyextending interior keyway 146 is angularly aligned with the small slip27 which is permanently secured to the mandrel core 19. Hand wheel 162is then operated to rotate the not :149 and threadably engage the collar1% there-with. As the collar engages the nut, its mold end moves axiallyto bear against the slips 23, 29 and 31 but not against slip 27, as thismember is aligned with the keyway 146. It will be readily seen thatafter this is done, the collar 144 is fixed against axial movementrelative to the mold 76 and the rails 104.

In FIGURE 11 the collar 14% is illustrated as approaching, but nothaving yet reached, its final position of abutment with the slips 2 8,29 and 30. It will be noticed that further appropriate rotation of thenut 149 will move the collar 144 closer to the mandrel assembly 9, thatis,

until the para-annular abutment 145 is fast against the slips 28, 29'and 39. Then the collar will be unable to move further unless the secondframe 192 is moved away from the mold assembly 76. It should be notedthat when the collar is so abutting the mandrel assembly 10, the end ofthe collar, in the area of the counterbore, will extend a short distanceinto the space between the exterior of the mandrel assembly 10 and theinterior of the mold 76. The reinforcement element formation 60 willnecessarily be distorted and compressed by this, but only along thesmall portion immediately affected and, as will be evident hereinafter,distortion is only temporary and the reinforcement element will usuallyspring back to its ordinary position after the collar 144 is removedfrom the area.

' As has been described hereinabo ve, the interior diameter of thecollar .144 is slightly greater than the exterior diameter of themandrel core 1t and it will therefore be seen that when, in accordancewith this invention, the mold-feeding carriage M6 is moved along railsM4, by air motor 132, away from the mold 76, the mandrel core 10,together with the fixed slip 27, will then be withdrawn from theimmobile mold, through the lumen of the immobile collar, While the slips28, 29 and 30 are held fast in their position within the mold because oftheir abutting relation with paraaan-nular shoulder 14 of the collar.

The means for supporting the mandrel assembly 9 prior to its insertionwithin the mold 76 and the means for supporting the mandrel core 10after its withdrawal from the mold will now be described. Referring toFIGURES 5 and 6, the mandrel support rollers 136 are, when in theiroperative position, located midway between rails 19-4- and at a levelslightly below the upper surface thereof. Each set of rollers 136consists of an opposed pair of spaced coaxial truncated-conical rollershaving their minor end-s facing one another. As is best shown in FIGURE5, when the mandrel support rollers 136 are operatively positioned at alevel to support a mandrel assembly, and particularly a mandrel assemblyof relatively small diameter, they will necessarily be located withinthe longitudinal path of the mold-feeding carriage 116. It is thereforewithin the contemplation of this invention to provide means for movingthe mandrel support rollers 136 from their usual position when themold-feeding carriage passes by.

To effect this end, each of the rollers 136 are rotatably mounted at thefree end of one of two rocker arms 169 which extend, in spaced parallelrelation, radically outward from a rocker arm shaft 171 which isrotatably mounted in suitable bearings (not shown) to extend under, andtransversely of, the rails 184.

An operating arm 175 is fixed to rocker arm shaft 171 and extendsradially therefrom. in the preferred embodiment illustrated thisoperating arm is angularly displaced from the rocker arms 169, and ispivotally connected to a drive rod 179 which is, in turn, pivotallyconnected with a piston rod 1811 of pneumatic cylinder 18-3. Thepneumatic cylinders 183 may be selectively operated from the operatingpanel 1115 at such times as the moldfeeding carriage 1.16 approaches agiven set of mandrel supporting rollers 136, or, as in this preferredembodiment, this operation may be entirely automatic by the provision ofsuitable mechanically operated valves (not shown), such as are wellknown in the art and need not be defined or described in detail herein,which energize the pneumatic cylinders to lower a particular set ofrollers 136 as the mold-feeding carriage approaches.

It should be noted that the opposed truncated ends of the mandrelsupport rollers 136 are spaced from one another a distance sufficient toallow clearance of the drive chain 120 when the opposed rollers movedownward, as a unit, through an arc defined by the movement of therocker arms 169. While the preferred embodiment illustrated in FIGURES 5and 6 has two sets of mandrel support rollers 136 it should heunderstood that it may be desirable to provide additional sets ofrollers, particularly when the pipe to be cast, and hence the mandrelassemblies 9, are unusually long. In such a case, each set of mandrelsupport rollers would be provided with means for lowering the rollersbelow the path of the passing mold-feeding carriage 1 16 which aresimilar to the means which has just been described.

After the mandrel core it) has been wholly withdrawn from the mold 76,hand wheel 143 is manipulated to release the thread 141 from thethreaded aperture 18 of the mandrel core so that the latter can then beremoved. At this time the second frame 162 is moved longitudinally, ofthe base frame ill, away from the mold 76 a suflicient distance toprovide ample clearance between the end of the mold and the collar 144,and the latter is released from the nut 149 and placed in its originalposition on the tube 138. This may be done by hand or, in thealternative, the mold-feeding carriage 116 can be moved forwardly, or inthe direction of the molds 76, so that the tube 138 extends through thecollar 144, and is keyed thereto, before the latter is disengaged fromthe nut 149 by suitable manipulation of hand wheel 161.

When the mandrel core 19, together with the fixed slip 27, is removedfrom the mold 76, the pins 39 of the remaining slips, i.e., slips 28, 29and 30, are, in effect, withdrawn from their respective sockets in themandrel core. As they no longer form a complete tube or sleeve, theywill then collapse and fall to the bottom of the interior of the mold.After the second frame 102 is longitudinally moved away from the mouthof the mold, and either before or after the collar 144 is disengagedfrom the nut 149, the entire mold-feeding assembly is movedtransversely, by suitable manipulation of operating wheel 78, to aposition where it is clear of the mouth of the mold. The slips 28, 29and 39 are then removed, either by hand or suitable power machinery (notshown), from the mold.

As will be readily understood, in withdrawing the individual slips fromthe mold, care should be exercised lest the fibers of the reinforcementelement 60 be disturbed and disarranged from their normal positions. Ashas been explained in the copending applications hereinabove mentioned,the quality and strength, and hence the end performance, of fibrouslyreinforced plastic pipe is quite dependent of the accuracy and precisionof placement of the fibers of the reinforcing element. It will now beseen that the use of the mandrel assembly 9 in the particular mannerdescribed hereinabove constitutes a marked improvement over thepreviously known apparatus and methods of inserting woven tubularreinforcement elements within a mold, inasmuch as it makes itunnecessary to slide a mandrel against the interior of the closefittinginnermost ply or layer of the reinforcement element 60. It has beenfound that when an ordinary mandrel is used, it frequently occurs thatthe weight of the mandrel on the lower portion of the reinforcementelement causes the latter to bunch, and thus reduces the inside diameterof the element until it finally seizes the mandrel, particularly whenthe mold is quite long. Even if the mandrel is not seized, the bunchingof the reinforcement element distorts the arrangement of the fibers sothat they are no longer disposed in the desired patterns, and a plasticimpregnated pipe formed therewith may be materially weakened.

The Mold Assembly It is within the contemplation of this invention thatthere be provided a number of molds, generally indicated at 76, arrangedin aligned rows to be serviced by the mold-feeding assembly 63, whichhas been already described, and which will also be serviced by a singlemoldejecting assembly 263 (FIGURES 18, 19 and 20), which will bedescribed in detail hereinafter.

Referring to FIGURE 12, in each mold assembly 76 there is an elongatedtubular casting mold 162 rotatably supported by ball bearings 163, orother conventional low friction means, within the lumen of a fixedtubular heating chamber 16%. The end of the mold 162 opposite to the endwhich receives the mandrel assembly is counterbored, at 165, andinteriorly fitted with an annular collar res, which is exteriorlydimensioned to fit into the counterbore, and has an interior diameterequal to the bore of the mold. If the pipe to be cast is to have one endexteriorly threaded, the collar 166 may have a threaded interior so asto act as a thread mold. The ends of the mold 162 extend a shortdistance beyond the ends of the heating chamber 164 so that, during thecasting operation, the mold can be partially closed by externallythreaded caps 167, each having a centrally disposed aperture 168therein. At or near the ends of the heating chamber 164, O-ring liquidseals 17% engage the outer periphery of the mold 162 and the innerperiphery of the chamber so that the lumen of the heating chamber isliquid tight even when the mold is being rotated in a manner which willnow be described.

At one end of the mold 162, and in a preferred embodiment at the mouthor the end which receives the loaded mandrel, a V-belt pulley 172 isnon-rotatably fixed, by bolts 173, to the mold coaxially therewith. ThisV-belt pulley is engaged, by a number of V-belts 174, to a suitabledrive wheel 176 on the shaft of a prime mover 178, which may be mountedabove the heating chamber. A portion of the junction of the Mach pulley1'72 and the exterior of the mold 162 defines an annular recess 18%having its female arcuate surface threaded to engage the exteriorlythreaded cap too which partially closes the mouth of the mold. The othercap 165, fitted at the other end of the mold 162, engages a similarlythreaded recess 182 formed in the built-up end of the mold.

Each heating chamber 164 is provided with one or more heating fluidinlets 134 and outlets 186 so as to allow a carefully controlledcirculation of heated fluid, which preferably is oil, from a fluid heatexchanger 183. The heat exchanger 188 may be of any conventional designand will not be described in detail, it being enough to say the heatexchanger is designed and arranged to retain a relatively large amountof heating fluid at a carefully controlled temperature level so thatthere is always a suihcient supply of heating fluid available at theexact temperature desired. In the centrifugal casting of reinforcedplastic impregnated pipe, it has been found that exact temperaturecontrol is often critical and this end can only be achieved bymaintaining an adequate supply of fluid, at the proper temperature,available at all times. While the fluid is hereinabove termed a heatingfluid, it should be observed that during the time of the exothermicreaction of the plastic pipe being formed in the mold, the moldtemperature may temporarily increase to a point whereby the fluidbecomes a cooling fluid, i.e., the mold temperature may rise above thatof the fluid.

The proper temperature of the heating fluid will vary from 150 to 350 F,depending on the character of the resin being used. When working withcertain resins, it may be desirable to pump heating fluid out of theheating chamber 164 after the resin has begun its thermosettingreaction, and replace it with a cooling fluid, also preferably oil, tocarry off the exothermic heat generated. Also, as certain epoxy resinsmust be cured at a fairly high temperature, i.e., approximately 320 F,it may be desirable to use other means than air cooling (which will bedescribed hereinafter) to get the temperature of the formed plastic pipedown to a point where the pipe is strong enough to be removed from themold 16?...

To achieve this end there is provided a fluid-cooling heat exchanger19%, which is equipped with conventional cooling means (not shown) tocontrol the temperature of the cooling fluid. While a preferredembodiment of this invention includes a row of transversely aligned moldassemblies '76, it is within the contemplation of this invention thatthe mold assemblies be paired, with each pair having a commonfluid-heating heat exchanger 188 and fluid-cooling heat exchanger 1%.Each fluid temperature control system includes suitable valves,reversible pumps, sumps, meters, and temperature indicia means which maybe of conventional design well known in the art and which, therefore,need not be illustrated or described in detail.

As the preferred heating and cooling fluids are oil, this fluid servesto lubricate, as well as control the temperature of, ball bearings 163,and, in such a case, no other lubrication is needed.

The Resin impregnating Means As shown in FIGURES l2 and 13, adjacenteach end of the mold assembly 76 there is a resin reservoir 2% hich ispreferably large enough to contain suflicient resin for preparing alarge number of plastic pipes. The reservoir 2% is mounted above thelevel of the mold assembly, so as not to interfere with other movingelements in the vicinity and, in a preferred embodiment, is suspendedfrom the ceiling structure (not shown). The reservoir may be a vessel ofany conventional design, although it should have a large removable cover202 to allow easy access for cleanin and loading and should includeheating coils 2&4 for maintaining the liquid resin at a predeterminedtemperature so as to control the viscosity thereof. Compressed air issupplied to the top of each reservoir by conduit 2435, so that liquidresin may be forced out under pressure through flexible conduit 206 tonozzle 2&8. The nozzles may have selectively variable openings, but itis within the contemplation of this invention that they be given aconstant fitting or opening for use with resin of a given viscosity andin conjunction with a mold 162 of a given length.

After the reinforcement element oil has been properly placed in the moldby the apparatus and methods described hereinabove, the nozzles 2% areinserted into the apertures .58 in the mold caps 167 (FIGURES l2 and 13)and the resin is then injected into the mold, by the operation of an airconduit control valve 216. With the proper combination of air pressure,resin viscosity, and nozzle opening, some of the air-borne stream ofresin from each nozzle will reach a point half way through the mold.

In a preferred embodiment of the invention, the resin is introduced intothe mold 162 while the latter is rotating at a high rate of speed,derived from the energization from the prime mover 178 (FIGURE 12). Forexample, in the manufacture of 3 inch O.D. pipe, it has been found thatthe mold should be rotated at approximately 1800 r.p.m., although itwill be understood that when the larger pipes are being cast, the samecentrifugal forces may be obtained at a lower rpm. As the mold rotates,and the liquid plastic material is being centrifugally urged todistribute itself evenly along the internal periphery of the mold 162,and hence, within and about the fibrous formations of the reinforcementelement 6%, the heat of the heating fluid within the chamber 164 (FIGURE12), which surrounds the major part of the mold 162, causes athermosetting reaction of the resin. it is well known that thistherrnosetting reaction will, in due course, be accompanied by a certainexothermic reaction on the part of the resin as it becomes set in itsfinal physical form. While the heating fluid will serve to carry off acertain amount of this exothermic heat, it is within this contemplationto provide additional means for achieving this end, as it is notpossible to remove the formed pipe from the mold until its temperaturehas been reduced to a vicinity of 120 F., and, further, as thisexothermic heat may, in some circumstances, have a deleterious effect onthe pipe being formed.

Air Blowing Assembly It is within the contemplation of this invention toprovide each mold assembly 76 with an air blowing assembly, generallyindicated at 226 (FIG RES l4, l5 and 16),

.53 which is arranged to blow air alternately through one end of mold162 and then through the other. It has been found that a greateruniformity of product is effected by alternating the direction of airflow so that all areas of the newly formed, fibrously reinforced plasticpiping are more uniformly treated.

Each air blowing assembly includes a blower 222 operated by a primemover 224 through a variable speed belt and pulley apparatus, generallyindicated at 226. The blower 222 discharges into an upwardly extendingduct 228 which splits, at a Y connection 230 into two branches, each ofwhich extend to the respective ends of the mold assembly (shown inphantom) at 76.

As each branch is substantially identical, only one will be described indetail. The ends of each of the arms of the Y ducts 230 are fitted witha disc valve 232 which discharges into a horizontally extending duct234. Duct 234 is fitted to the disc valve 232 by a suitable sleeveconnection which allows this duct to rotate freely, about its own axis,while the valve remains immobile, and is also supported by a bearing 236located in spaced relation to the valve. Another duct 238 is connectedto the free end of duct 234 to extend generally downward and thence backtowards the center of the air blowing assembly, and terminates in amouth 240 which is dimensioned to ap proximate the aperture in the cap167 of the molding assembly 76, the last mentioned elements being shownin the phantom. The entire air blowing assembly 226 is so dimensionedthat the mouths 24d of each branch are spaced apart a distance onlyslightly greater than that of the overall length of the mold assembly76.

As best shown in FIGURE 14, the air blowing assembly is placed to oneside of the mold assembly 76, and when the downwardly extending duct 238hangs in a plumb line, its mouth 24% is well clear of the mouth of themold, so as not to interfere with the loading or unloading thereof.

The rotatably mounted duct 234 has a radially extending operating arm241 fixed thereto, and the free end of this arm is connected to thevertically extending piston rod 242 of pneumatic cylinder 244, thelatter being pivotally mounted on the base of the air blowing assembly.As is evident in FIGURES 14, and 16, extension and retraction of thepiston rod 242 will cause duct 234 to oscillate about its own axis and,further, will cause the duct 238 to swing from a plumb position to anoblique position (illustrated in phantom in FIGURE 16) and then back toplumb. The various elements are so dimensioned and arranged that upon afull extension of piston rod 242, the mouth 24% of the duct 238 will bealigned with, and adjacent to, the aperture in mold cap 167.

The disc valve 232 is of conventional design and is operated by rotatingan internal disc, having an off-center aperture 2-45 (in phantom, FIGURE16), into and out of a position wherein the aperture is aligned withcoaxial intake 246 and discharge 247 fittings (FIGURES 14 and 15). Inthe present apparatus, the disc is caused to rotate about its axis bythe arcuate movement of a pin 243 extending outwardly from the valve 232on the same side as the operating arm 241. The pin 248 extends into anelongated slot 250 formed in the operating arm 241 so that it movestherewith. It will therefore be seen that the swinging of the duct 234into a position whereby its mouth 249 is aligned with the cap 167 of themold assembly 76 will also effect an opening of the disc valve 232, andthat when the duct 238 is moved back to a plumb position, the valve willclose.

It is within the contemplation of this invention to arrange a system oftimer-earn operated valves to supply pressurized air alternatively toone pneumatic cylinder 244 and then to the other in a timed cycle, ofsay one minute, so that each of the ducts 238 will alternatively swinginto alignment with its end of the mold assembly 76 and then deliver aone minute blast of air while the other duct 238 is maintained in aposition clear of the id mouth of its end of the mold. It is furtherwithin the contemplation of this invention that there be provided amanually operated bleeding valve to allow both arms to swing to a piumbposition, with each disc valve 232 being closed, when the mold assembly76 is being loaded or unloaded, or is not in use.

Such a system is shown schematically in FIGURE 15, in which timer 252alternatively opens valves 254 leading to the respective pneumaticcylinders 244. The manually operated bleeding valves 25-5 are interposedin the pressure lines intermediate the valves 254 and the pneumaticcylinders 244. It should, of course, be understood that the overridingvalves 256 could also be connected with timing apparatus if the loadingand unloading operations are to be part of a timed cycle.

While the thermosetting reaction of the material within the mold hasbeen heretofore described as occurring as a result of the temperature ofthe heating fluid in the heating chamber 164, it is within thecontemplation of this invention that the air blown through the mold 162may be heated when certain resins are being used in the castingoperation. Accordingly, electric heating coils 260 (FIGURE 16), or otherair heating means, may be installed at the intake of the blower 222 sothat the air supplied to the interior of the mold 162 will be warm.

The Pipe Ejecting Assembly Referring to FIGURES 18, 19 and 20', it willbe seen that the pipe ejecting assembly, generally indicated at 268,includes an elongated base frame, generally indicated at 279, which ismounted on flanged wheels 272 for movement along relatively transverselyextending fixed rails 274, so that the entire pipe ejecting assembly canbe transversely moved between a number of positions corresponding to anumber of the casting molds generally indicated at 76.

In a preferred embodiment, the transverse movement of the entire pipeejecting assembly 268' is selectively controlled by hand operatedsprocket wheel 278- which is connected by chain drive 28% to a sprocket282 on the shaft 284, upon which the weels 272 are non-rotatablymounted. As will be evident, hereinafter, it is quite important that theentire pipe ejecting assembly 268 be properly aligned with the axis ofthe particular mold which it is to service, and means for attaining thisexact alignment include an air lock assembly generally indicated at 286which is identical with the air lock assembly 86 described in detailhereinabove in the disclosure of the mold-feeding assembly 68. That isto say, the air lock assembly 285 includes a pneumatic cylinder 288having a piston rod 2% maintained in a position to selectively engage anaperture in one of the rails 274 when the pneumatic cylinder is suitablyenergized by operation of valve 296' on operating panel 298.

The transversely movable base frame 270, which consists essentially of apair of suitably braced, longitudinally extending, spaced parallel rails30%, which may be formed of I-beams or the like, has a second frame,generally indicated at 302, which consists essentially of a pair ofsuitably braced, longitudinally extending, spaced parallel rails sea,which may be formed of I-beams or the like, mounted thereon. The secondframe 3&2 is supported on flange wheels 306 which are arranged to rollalong rails 300 when the second frame is moved longitudinally of thebase frame 270. Such movement is obtained by a pneumatic cylinder 308,depending from the second frame 302, having the free end of its pistonrod 310 fixed to a fixed upstanding member 312 on the base frame 270'.The pneumatic cylinder 308 is double acting and is coupled, by suitablelines, to a three-way control valve 3-14 located on the operating panel298.

A pipe-ejecting carriage, generally indicated at 3 16, is disposed uponthe rails 304 to move longitudinally thereof on wheels 318. Thepipe-ejecting carriage 3 1 6 is positively actuated to movelongitudinally of second 1 5 frame 3-92 by a chain drive 32% extendinglongitudinally of the rails 36 2-, and approximately midwaytherebetween, at a level slightly below their upper surface. The chaindrive 3% is secured, at each end, to the pipe-ejecting carriage 316, asby draw bolts 322 (FIGURE 20), and extends around an idler sprocket 324mounted at the mold end of the rails 384 and around a power sprocket 326mounted at the opposite end of these rails. The power sprocket 326 isnon-rotatably fixed to the shaft of reversible air motor 332, which isremotely controlled by a four-way valve 334 located on the operatingpanel 298.

As the pipe-ejecting carriage 316 serves to convey a section of newlyformed plastic pipe 335, there are provided several pipe-supportingrollers 3-36 to bear the weight of, and to support, the pipe during theperiods when it is on, or partially on, the pipe ejecting assembly 263.These pipe-supporting rollers are substantially identical with themandrel-supporting rollers 136 described in detail in the disclosure ofthe mold-feeding assembly 68, and each are, when in their operativeposition, located midway between the rails 36 i and at a level slightlybe low the surface thereof.

Each set of rollers 336 consists of an opposed pair of spaced coaxialtruncated conical rollers having their minor ends facing each other. Asis best shown in FIGURE 18, when the pipe-supporting rollers 336 areoperatively positioned at a level to support a newly formed pipe 335,and particularly a pipe of relatively small diameter, they willnecessarily be located along the longitudinal path of the pipe-ejectingcarriage 316. It is therefore within the contemplation of this inventionto provide means for moving the pipe-supporting rollers 336 from theirusual position when the pipe-ejecting carriage passes by.

To effect this end, each of the rollers 336 are rotatably mounted at thefree end of one of two rocker arms 370 which extend, in spaced parallelrelation, radially outward from a rocker arm shaft 372 which isrotatably mounted in suitable bearings (not shown) to extend under, andtransversely of, the rails 3'84. An operating arm 376 is fixed to therocker arm 372 and extends radially thereof. In the preferred embodimentillustrated, this rocker arm is angularly displaced from the rocker arm370 and is pivotally connected to a drive rod 380 which is, in turn,connected with a piston rod 382 of pneumatic cylinder 384. The pneumaticcylinders 384 may he selectively operated from the operating panel 298at such times as the pipe-ejecting carriage 316 approaches a given setof pipe-supporting rollers 336, or, as in this preferred embodiment,this operation may be entirely automatic by the provision of suitablemechanically operated valves, such as are well known in the art and neednot be described in detail herein, which operate the pneumatic cylindersto lower the rollers 336 as the pipe-ejecting carriage 316 approaches.

it should be noted that the opposed truncated ends of thepipe-supporting rollers 335 are spaced from one another a distancesufficient to allow clearance of the chain drive 32% when the opposedrollers move as a unit, through an arc defined by the movement of rockerarms 379. While the preferred embodiment illustrated in FIG- URES 18 and19 has two sets of pipe-supporting rollers 356, it should he understoodthat it may be desirable to provide additional sets of rollers,particularly when the pipe being ejected from the mold 76 is unusuallylong. In such a case, each set of pipe-supporting rollers would beprovided with means for lowering the rollers below the path of thepassing pipe-ejecting carriage 31d which are similar to the means whichhave just been described.

Referring more particularly to FlGURE 20, mounted upon the pipe-ejectorcarriage 316 is a pipe-ejector pullout. As has been describedhereinbefore, the end of the pipe mold 162 nearest the pipe-ejectingassembly 268 is counter-bored and loosely fitted with a reinforcingcollar 156, usually having an internal diameter equal to that of therest of the mold, although it may have a threaded interior if threadedpipe is being cast. Generally speaking, the pipe-ejector pulloutconsists of an axially expanding circular wedge which is inserted withinthe lumen of the newly formed pipe 335 and then expanded to bear againstthe inner periphery thereof. The pipe is not distorted or injured as ithas been cast in a closely fitted relation to the reinforcing collar166. A hydraulic jack mounted on the pipe-ejecting carriage is henenergized to urge the expanded wedge, and the pipe and reinforcingcollar grasped thereby, toward the mold-ejecting carriage. The movementimported by the hydraulic jack is relatively short, it being sufiioientthat the entire length of newly cast pipe be moved a short distance soas to break the typical initial bond or adhesion between the pipe andthe mold ltd-2. The pipe is then completely withdrawn from the mold bythe use of a powerful winch to draw the pipe-ejecting carriage along therails 304. This apparatus will now he described in detail.

As shown in FEGURE 20, a cylindrical sleeve 400 mounted upon carriage316 has a snugly fitting operating rod 492 extending itherethrou gh. Atube 404 is coaxially cantilevered from the sleeve 400, and extendstoward the mold assembly 76. The tube 494 has a longitudinally extendingkeyway 4 9 6 therein and has an interior diameter somewhat greater thanthe exterior diameter of operating rod 402. Slidably mounted and keyed(by key 4&7 fitting in keyway 496) within the tube 4M- is a sleeve 43%which is interiorly dimensioned to receive the operating rod MP2 and hasat least a portion of its lumen interiorly threaded to engage raisedthreads 410 formed upon a portion of the operating rod. The free end ofthe operating rod nearest the mold assembly 7 6 is reduced and formedwith a truncated conical projection 412 which dares outwardly toward thefree end thereof. The opposite end of the operating rod extends througha hollow hydraulic jack, generally indicated at 414, and has anoperating wheel 416 fixed on the extreme end.

The conical projection 412 is provided with a segmental colla-r ringcomposed of four chordal elements 418 (FIGURE 21) held together, andabout the conical projection, by a tension spring member 4-20 disposedin a peripheral groove 422. The segmental collar ring is formed with aninterior taper complimentary with that of the conical projection 412 andhas an exterior peripheral surface defining a right cylinder. In apreferred embodiment, the exterior or peripheral surface of each chordalelement is formed with a number of fine serrations thereon so as to giveit a better grip on the interior periphery of the pipe 335, as will beexplained. In ope-ration, the conical projection 412, circumscribed bythe segmental ring 413, is inserted within the end of the mold 162 andso located that the segmental ring is within the area thereof which isfitted with the reinforcing collar 156. Rotation of operating rod 492,by suitable manipulation of wheel 4-16, causes an axil movement thereof,away from the mold 1-62, due to the engagement or the thread 410 withthe threaded interior of keyed, and hence non-rotatable, sleeve 4%8. Theseg mental collar ll-8, which is biased by tension spring 429 to snuglyfit on the conical projection 412, moves towards the sleeve 4'33 untilits end abuts the planar end surfaces of the sleeve. Further axialmovement of the operating rod 492, and the conical projection 412, inthe same direction, will cause the respective elements of the segmentalring to ride up the conical element until its peripheral surfacecontacts the interior of the pipe 335. It will now be seen that oncesuch contact is made, further axial movement of the operating rod 4&2will serve to Wedge the serrations on the peripheral surfaces of thesegmental ring 418 tightly against the interior of the of the sleeve 4%,so that the end of the segmental ring above, the strong reinforcingcollar 166 snugly circumscribes this portion of the pipe 335 so there isno danger 17 of distorting or injuring the pipe as long as reasonableforces are used. It will now be understood that the minor interiordiameter of the conical projection 412 must be less than the interiordiameter of the free end of the sleeve 408, so that the end of thesegmental ring 'will properly abut the latter.

At this time the hollow hydraulic jack 414 is energized to urge the hub420 of the operating wheel 416 away from the pipe-ejecting carriage 316.This movement will be experienced by the conical projection 4-12 and thesegmental ring 418 and will tend to pull the pipe 335 out of the mold162. As has been stated hereinbefore, this movement is only for a verylimited distance, it being quite sufiicient that the pipe be movedenough to break the bond or adhesion between the newly cast pipe 335 andthe mold 162.

As shown in FIGURES 18 and 19, a winch 430, powered by a prime mover432, is mounted at the end of second frame 362 furthest from the moldassembly 76, and a cable 436 is rove about the winch. The free end ofthe cable 436 is fitted on pipe-ejecting carriage 316 and is utilized todraw the latter along rails 304, and, hence withdraw the newly cast pipe335 from the mold 162 after the hydraulic jack 414 has been operated tobreak the initial bond or adhesion between the pipe and the mold. Whenthe winch is being operated, the reversible air motor 332 is vented bythe operation of valve 334 so that the motor offers no resistance to thewinch. In a preferred embodiment, the operating controls 438 for thewinch may be located on the operating panel 298 alongside the valve 334.As the pipe-ejecting carriage moves away from the mold, thepipe-supporting rollers 336 will rise to their operative position toprovide suitable support for the length of the pipe 335 being withdrawnfrom the mold in a manner similar to the action of the mandrel supportrollers 136 described hereinabove.

After the pipe has been completely withdrawn from the mold, theoperating wheel 416 is rotated to relax the grip of the segmental collarring 418 on the inner periphery or" the pipe, in a manner that will nowbe understood, and then the pipe-ejecting carriage is moved away fromthe pipe a distance sufiicient to clear the conical projection 412 andthe segmental ring 418 from the interior of the pipe. The pipe is thenremoved from the pipe-ejecting assembly 268, by any suitable means, andthe pipeejecting carriage is moved back to the mold end of the secondframe 3% by the air motor 332 and the chain 3253 so as to be ready tobegin a new pipe-ejecting operation.

In FIGURES l8 and 19, the second frame 302 is illusstrated as being sopositioned as to be spaced from the mold assembly 76, when the pipe 335is being withdrawn from the mold 162. It should be understood, however,that when the hydraulic jack 414 is being operated to break the bondbetween the mold and the pipe, the mold end of the second frame 302 ispositioned to abut the end of the mold 162; otherwise the pulling forceof the jack would have a tendency to pull the mold 162 out of the moldassembly 76.

This application is a division of co-pending application Serial No.594,565, filed June 28, 1956, now Patent No. 2,997,737.

Having described only a typical preferred form and application of ourinvention, we do not wish to be limited or restricted to specificdetails herein set forth but wish to reserve to ourselves any variationsor modifications that may appear to those skilled in the art and fallingwithin the scope of the following claims:

We claim:

1. Apparatus for the insertion of a fibrous elongated hollowreinforcement element formed about a mandrel into a mold so dimensionedas to closely fit the reinforcement and for subsequently withdrawing atleast a portion of the mandrel from the mold to leave the reinforcementelement therein comprising: a first frame mounted for selective movementtransversely of the mold on a path adjacent the mouth thereof; a secondframe mounted for selective movement longitudinally of said first framein a direction parallel to the axis of the mold; carriage means mountedfor selective movement longitudinally of said second frame in adirection parallel to the axis of the mold; selectively operable mandrelengaging means mounted on said carriage, and means for maintaining thereinforcement element within the mold when the mandrel engaging means isoperated to withdraw at least a portion of the mandrel therefrom.

2. Apparatus for the insertion of a fibrous tubular reinforcementelement formed about a mandrel assembly consisting of a mandrel coresurrounded by a plurality of slips into a mold so dimensioned as toclosely fit the rein forcement element and for subsequently withdrawingthe mandrel core from the mold to leave the reinforcement elementtherein comprising: a first frame mounted for selective movementtransversely of the mold on a path adjacent the mouth thereof; a secondframe mounted for selective movement longitudinally of the first framein a direction parallel to the axis of the mold; carriage means mountedfor selective movement longitudinally of said second frame in adirection parallel to the axis of the mold when the second frame isaxially aligned with the mold; selectively operable mandrel engagingmeans mounted on said carriage; and slip abutting means engageable withsaid second frame in a position to abut the slips of a mandrel assemblydisposed within the mold when the mandrel core is being withdrawn fromthe mold by the mandrel engaging means, the arrangement being such thatthe axial movement of the mandrel engaging means is independent of theslip abutting means when the latter is engaged with second frame.

3. Apparatus for the insertion of a fibrous tubular reinforcementelement formed about a cylindrical mandrel assembly consisting of acylindrical mandrel core surrounded by a plurality of slips into a moldso dimensioned as to closely fit the reinforcement element and forsubsequently withdrawing the mandrel core from the mold to leave thereinforcement element therein comprising: a first frame mounted forselective movement transversely of the mold on a path adjacent the mouththereof; a sec ond frame mounted for selective movement longitudinallyof the first frame in a direction parallel to the axis of the mold;carriage means mounted for selective movement longitudinally of saidsecond frame in a direction parallel to the axis of the mold when thesecond frame is axially aligned with the mold; cylindrical selectivelyoperable mandrel engaging means mounted on said carriage; a tubular slipabutting means engageable with said second frame in a position to abutthe slips of a mandrel assembly disposed within the mold when themandrel core is being withdrawn from the mold by the mandrel engagingmeans, the arrangement being such that the mandrel engaging means canmove axially through the lumen of the slip abutting means when thelatter is engaged with said second frame.

4. Apparatus for theinsertion of a fibrous tubular reinforcement elementformed about a cylindrical mandrel assembly consisting of a cylindricalmandrel core surrounded by a plurality of slips into a mold sodimensioned as to closely fit the reinforcement element and forsubsequently withdrawing the mandrel core from the mold to leave thereinforcement element therein comprising: a first frame mounted forselective movement transversely of the mold on a path adjacent the mouththereof; a second frame mounted for selective movement longitudinally ofthe first frame in a direction parallel to the axis of the mold;carriage means mounted for selective movement longitudinally of saidsecond frame in a direction parallel to the axis of the mold when thesecond frame is axially aligned with the mold; cylindrical selectivelyoperable mandrel engaging means mounted on said carriage; a tubular slipabutting collar dimensioned to be axially slidably mounted on saidmandrel engaging means and having an interior diameter less than theexterior diameter of the mandrel assembly and at least as great as theexterior diameter of the mandrel core; and means for engaging saidcollar against axial movement relative to said second frame, wherebysaid collar may be held immobile against at least some of the slips ofthe mandrel assembly within the mold when the mandrel core is being withdrawn from said mold and through said collar by moyement of the carriagemeans and the mandrel engaging means away from the mold.

5. Apparatus for the insertion of a fibrous tubular reinforcementelement formed about a cylindrical keyed mandrel assembly consisting ofa cylindrical mandrel core surrounded by a plurality of slips into amold so dimensioned as to closely fit the reinforcement element and forsubsequently withdrawing the mandrel core from the mold to leave thereinforcement element therein comprising: a first frame mounted forselective movement transversely of the mold on a path adjacent the mouththereof; a second frame mounted for selective movement longitudinally ofthe first frame in a direction parallel to the axis of the mold;carriage means mounted for selective movement longitudinally of saidsecond frame in a direction parallel to the axis of the mold when thesecond frame is axially aligned with the mold; cylindrical selectivelyoperable mandrel engaging means mounted on said carriage; a tubular slipabutting collar dimensioned to be axially slidably mounted on saidmandrel engaging means and having an interior diameter less than theexterior diameter of the mandrel assembly and at least as great as theexterior diameter of the mandrel core; a key on the exterior of saidmandrel engaging means; and a complementary longitudinally extendingkeyway formed in the interior of said collar, said keyway being of awidth and height to receive said key and also to receive the key on themandrel core.

6. The apparatus defined in claim and further including means forsupporting a mandrel assembly being inserted into the mold and forsupporting a mandrel core being withdrawn from the mold, said meansbeing mounted on said second frame and being arranged to avoidinterference with the selective movement of said carriage means and themeans mounted thereon.

7. The apparatus defined in claim 5 and further including means forsupporting a mandrel assembly being inserted into the mold and forsupporting a mandrel core being withdrawn from the mold, said meansbeing mounted on said second frame; means to maintain said when themandrel assembly or the mandrel core are adjacent thereto and tomaintain said last-mentioned means clear of the path of the carriagemeans when the latter is adjacent thereto.

8. The apparatus defined in claim 7 and further including means formaintaining said first frame in a fixed position relative to a moldbeing serviced by the apparatus when the mandrel engaging means is beingoperated, the position being defined by the axial alignment of the moldand the mandrel engaging means.

9. Apparatus for inserting a fibrous tubular reinforcement element intoany one of a plurality of parallel transversely aligned molds anddepositing the same therein in peripheral close-fitting contacttherewith including the combination comprising: a first frame mountedfor selective movement transversely of the molds on a path adjacent themouths thereof; a second frame mounted for selective movementlongitudinally of said first frame in a direction parallel to the axesof the molds; carriage means mounted for selective movementlongitudinally of said second frame in a direction parallel to the axesof the molds; a cylindrical mandrel assembly exteriorly diametricallydimensioned to closely fit the lumen of the reinforcement element, saidmandrel assembly including an elongated mandrel core, a plurality ofelongated slips disposed along the periphery of said mandrel core withtheir longitudinal axes parallel to the longitudinal axis of saidmandrel core, each of said slips having an inner surface facing saidmandrel core and an arcuate outer surface, the outer surfaces of theseveral said slips defining a cylinder constituting the peripheralexterior of the mandrel assembly, said slips being so formed andarranged that the cylinder defined thereby will collapse upon thewithdrawal of the mandrel core therefrom; selectively operable mandrelcore engaging means mounted on said carriage means to urge the mandrelcore into and out of the mold upon appropriate movement of the carriagemeans longitudinally of said second frame; and means operable when themandrel assembly, together with the reinforcement element are within themold to maintain the reinforcement element therein when the mandrel coreengaging means is operated to withdraw the mandrel core therefrom.

10. The apparatus defined in claim 9 in which the means to maintain thereinforcement element within the mold includes means to maintain atleast some of the slips therein when the mandrel core is being withdrawnfrom the mold, the arrangement being such that the cylinder defined bythe slips within the mold will collapse upon the substantial withdrawalof said mandrel core.

References Cited in the file of this patent UNITED STATES PATENTS1,482,446 Stevens Feb. 5, 1924 1,563,513 McNeill Dec. 1, 1925 2,297,648Cushman Sept. 29, 1942 FQREIGN PATENTS 426,172 Great Britain Mar. 28,1935

1. APPARATUS FOR THE INSERTION OF A FIBROUS ELONGATED HOLLOWREINFORCEMENT ELEMENT FORMED ABOUT A MANDREL INTO A MOLD SO DIMENSIONEDAS TO CLOSELY FIT THE REINFORCEMENT AND FOR SUBSEQUENTLY WITHDRAWING ATLEAST A PORTION OF THE MANDREL FROM THE MOLD TO LEAVE THE REINFORCEMENTELEMENT THEREIN COMPRISING: A FIRST FRAME MOUNTED FOR SELECTIVE MOVEMENTTRANSVERSELY OF THE MOLD ON A PATH ADJACENT THE MOUTH THEREOF; A SECONDFRAME MOUNTED FOR SELECTIVE MOVEMENT LONGITUDINALLY OF SAID FIRST FRAMEIN A DIRECTION PARALLEL TO THE AXIS OF THE MOLD; CARRIAGE MEANS MOUNTEDFOR SELECTIVE MOVEMENT LONGITUDINALLY OF SAID